Solar System Log by Andrew Wilson, published 1987 by Jane's Publishing Co. Ltd.

Lunar Orbiter 4 was the first in the series dedicated to scientific surveys of the Moon. After a burn at 21:54 UT on 8 May 1967, the spacecraft entered a 2,705 x 6,034-kilometer orbit inclined at 85.48 degrees, becoming the first vehicle to enter polar orbit around the Moon.

Controllers successfully overcame a problem with the Thermal Camera Door, and subsequently, during its two-month mission, the orbiter took pictures of 99 percent of the near side and 75 percent of the far side of the Moon in a total of 193 frames. The images had a resolution of up to 60 meters.

In early June, controllers lowered the spacecraft's orbit to match that of Lunar Orbiter 5 so scientists could collect gravitational data in support of the latter mission. Before losing contact on 17 July, Lunar Orbiter 4 took the first photos of the lunar south pole and discovered a 240-kilometer-long crustal fault on the far side.

Since contact was lost before controlled impact, the spacecraft naturally crashed onto the Moon on 6 October 1967 due to gravitational anomalies.